Study reveals why mushrooms may help prevent prostate cancer progression

Researchers at City of Hope®, one of the largest and most advanced cancer research and treatment centers in the United States, ranked among the top five cancer centers in the country by U.S. News & World Report, and a national leader in providing world-class, comprehensive support programs to cancer patients, now understand why taking an experimental button mushroom supplement shows promise in slowing and even preventing the spread of prostate cancer among men participating in a Phase II food-as-medicine clinical trial. In preclinical and preliminary data, City of Hope scientists found that taking button mushroom tablets reduced the number of myeloid-derived suppressor cells (MDSCs), which are associated with the development and spread of cancer.

"City of Hope researchers are studying foods like button mushrooms, grape seed extract, pomegranate, blueberries, and ripe purple jamun berries to see if they have potential medicinal properties. We're finding evidence that plant-based compounds may one day be used to support traditional cancer treatments and prevention," said Shiuan Chen, PhD, professor and chair of the Department of Cancer Biology and Molecular Medicine at City of Hope's Beckman Institute for Research and senior author of the new study, published in Clinical and Translational Medicine. "This study suggests that treatments using the 'food as medicine' concept may eventually become standard, evidence-based care for everyone facing cancer."

The use of natural therapies to treat cancer, called integrative oncology, is becoming increasingly popular as people become more health conscious and understand the benefits of a holistic approach to cancer care. Thanks to a $100 million donation from Panda Express CEOs Andrew and Peggy Cherng, the Cherng Family Center for Integrative Oncology at City of Hope is accelerating research, education, and clinical care to ensure cancer patients and their doctors have access to safe, proven treatments.

At City of Hope, lab researchers work closely with physicians to enable two-way research: lab discoveries are quickly translated into clinical practice, and patient observations are fed back to the lab to develop more effective cancer treatments.

In mouse models, the researchers found that administration of the button mushroom extract significantly slowed tumor growth and extended the lifespan of the mice. The extract also improved T-cell immune response by reducing MDSC levels, which increased the immune system’s ability to destroy cancer.

The researchers analyzed blood samples from some of the men participating in the Phase II clinical trial at City of Hope. These men were being actively monitored while taking button mushroom supplements. When they examined samples from eight participants before and after three months of button mushroom treatment, the scientists found a decrease in tumor-promoting MDSCs and an increase in T cells and natural killer cells, indicating that anti-cancer immune defenses were restored and cancer growth was slowed.

"Our study highlights the importance of seeking professional advice to ensure safety and avoiding self-prescribing supplements without consulting a physician. Some people purchase mushroom products or extracts online, but these are not FDA-approved. While our results are promising, research is ongoing. However, adding fresh button mushrooms to your daily diet won't hurt," said Xiaoqiang Wang, MD, PhD, a City of Hope researcher and first author of the study.

People interested in participating in a Phase II clinical trial funded by the National Cancer Institute can visit https://www.cityofhope.org/research/clinical-trials. City of Hope researchers are now focusing on whether reducing MDSC levels is associated with improved clinical outcomes in prostate cancer patients.